-LRB- CNN -RRB- -- It 's been a busy year for the British royal family . The Prince of Wales and the Duchess of Cornwall alone covered almost 48,000 miles to undertake 804 official engagements between April 2011 and the end of March this year . So who pays the bills ?

Prince Charles ' office at Clarence House released its annual review Friday , shedding light on how money is spent on the couple , as well as Princes William and Harry and , of course , the newest addition to the family , Catherine , Duchess of Cambridge .

As the queen 's eldest son , Charles , Prince of Wales , is mostly funded by the Duchy of Cornwall , a private estate consisting of more than 200 square miles of agricultural , commercial and residential land mostly in southwest England .

In the 2011-12 fiscal year , the prince 's private income from the duchy rose by 3 % to slightly more than $ 28.5 million . He received an additional $ 3.42 million in public funding from Parliament and government departments , a year-on-year increase of 11.8 % .

With more private and public income , Prince Charles ' household spending increased by 4.1 % to $ 15.3 million , and all 135 full-time staff members received a pay raise of 3 % . Nine of those employees work for Princes William and Harry , and for Catherine , Duchess of Cambridge .

So what is the expense of the royal family 's newest member ?

`` It 's actually quite minimal , '' said Prince Charles ' communications secretary , Paddy Harverson , `` There 's been quite a lot of focus on things like clothes but actually , when you look at the numbers , it 's mostly absorbed into the existing expenditure . ''

A royal aide added that it would be `` rather impolite '' to disclose how much money had been spent on the dresses that hit front pages of newspapers around the world every time Catherine steps out in public . What we do know , though , is that Prince Charles pays for his daughter-in-law 's outfits for official engagements out of his private income .

Anti-monarchy groups such as Republic have criticized the royal family for using public money to travel . `` Prince Charles gives little back to the country yet has a deeply held sense of entitlement when it comes to accessing public funds , '' Chief Executive Graham Smith said Friday . `` We believe time is long overdue that the government brought royal spending under proper control . ''

However , Harverson maintains : `` Members of the royal family do a huge amount of work . ... We really feel it 's fantastic value for money . As it happens , 90 % of it is his -LRB- Prince Charles ' -RRB- own income , so it 's not coming from central government coffers . ''

Royal aides champion the continued success of the prince 's group of 16 charities as the greatest example of the royal family giving back to the public . Between April 2011 and the end of March this year , the Prince of Wales directly or indirectly raised more than $ 200 million for his charities , which support young people , the environment and enterprise .

After last year 's royal wedding and the recent Diamond Jubilee celebrations , polls have showed that the British royal family is as popular as ever . Riding high on that wave is the household of the Prince of Wales , as exemplified by the 76,825 letters received from the public in 2011-12 . That is more than double the mail from the previous year .

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Clarence House releases its annual review of royal household costs

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Expenses of Catherine , Duchess of Cambridge , are `` quite minimal ''

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An anti-monarchy group says it is time to bring `` royal spending under proper control ''

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Clarence House calls the royal family a `` fantastic value '' for all the work they do